Telephone-station apparatus



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TELEPHONE STATION APPARATUS Patented 001;. 8, 1889.

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B. ABDANK-ABAKANOWICZ.

` TBLEPHONBSTATIONAPPARATUS. No. 412,580. Patented Oo't. 8, 1889.

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N. 412,580. Patented om. s, 1889.

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UNITD- STATES PATENT OFFICE.

BRUNO ABDANK-ABAKANOWICZ, OF PARIS; FRANCE, ASSIGNOR 'IO THE AMERICANBELL TELEPHONE COMPANY, OF BOSTON, MASSACHUSETTS.

TELEPHONE-STATION APPARATUS.

SPECIFICATION forming pm ofV Letters Patent No. 412,580, dated octobers, 1889.

Application filed February 20, 1889. Serial No. 300,543. (No model.)Patented in FranceIehruary 28, 1888, No. 189,018, and

K in Austria-Hungary Aprill, 1888, No. 6,623.

To @ZZ whom it may concern:

Be it known that I, BRUNO ABDANK-ABA- KANOWICZ, residing at Paris, inthe Republic vof France, have invented certain Improvementsin'Telephone-Station Apparatus, (fory which I have obtained LettersPatent in France, No. 189,018, dated February 28, 1888, and inAustria-Hungary, No. 6,623, dated April 16, 1888,) of Which the,yfollowing is a specification.

'This' invention relates to combination telephone sets in Which thevarious appliances are `organized in a small compass, so as to make acompact, neat, uncomplicated, and eflicient telephonie outfit suitablefor home use. The various instrumentalities which are practicallyrequired even in the simplest efficient installations are, in brief, atelephonie transmitter and receiver at each station for the transmissionand reproduction of speech, a call-bell for the reception ofcall-signals, a call-sending appliance for the transmission ofcall-signals, and a commutating switch or circuit-changer, whereby theline-circuit is transferable from the call-signal appliances to thetelephones, and vice versa. This latter device is usually dependent, atleast in part, upon the telephone-receiver, and it is usual to socombine the switch with the said receiver that the latter, when hung inits position of rest, is caused to exertaforce against the pressure of aspring and thereupon to actuate the switch in one direction, while thesaid spring acts,when the receiver is removed, to move the switch in theopposite direction.

In a separate application for a patent, iiled of even date'herewith andhaving the serial number 800,542, I have described and claimed themicrophonic transmitter, which forms one feature or element of theinvention described and claimed herein.4 The said transmitter comprisesa series ofv carbon disks standing on edge between an inclined plane ofconducting material and a conducting-plate, preferably of carbon,carried by a vibratory diaphragm, the said disks having necessarily atendency to roll down the said inclined plane, but being prevented fromcarrying the said tendency into effect by their contact with thediaphragm-plate, which holds them in 5o place. The current passesthrough the said disks and their respective front and rear contacts, andits strength is varied by variations in the resistance at said points ofcontact when the diaphragm is varied bythe voice of 5 5 an operator.

In the organization of appliances which forms the subject of my presentinvention all of the elements which I have stated as being requisite orconvenient in speech-trans- 6o mission are, with the exception of thecallbell, comprised. That instrument, however, can be, and preferablyis, affixed to any part of the wall, or, may, if preferred, be mountedout of sight. I

In the complex instrument which I am about to describe a mold, frame, orbase of non-conducting material is first provided, being recessed infront for'the reception of the transmitting-telephone diaphragm and 7omichrophonic contacts, and being suitably cut or pressed into channelson its rear side for the reception of the vvarious connectingwires,springs, and screws, and for the attachment of a call-key. Themicrophone is of the character indicated, and the diaphragm thereof issecured in its recess by a circular metal spring. Thereceiving-telephone does not essentially differ with respect to itsWorking parts from the ordinary magneto-tele- So phone, being, as usual,provided with a magnet, electro-magnetic coil, and a diaphragm mountedin inductive proximity to the coilsurrounded magnet-pole, the wholebeing inclosed in a suitable case and provided with a screw-capperforated to serve as an ear-piece. Itis, however, externally shapedlike a Watch, which it also resembles in size. It is provided With asuspending-stem in the form and position of a watch-stem, and this stemis 9o adapted to enter a perforated metal plate fastened tothe upperedge of the transmittercase. When the stem is so entered and thereceiver pressed downwardly so that it hangs vertically in front of thetransmitter-dia 9 5 phragm, concealing the same, it is in theplaceprovided for its reception when not in use, and it cannot beremoved therefrom except by first raising it to a position at rightangles with the transmitter, when it may be withdrawn for use, thecircuit of the receiver helix heilig connected by a exible conductFing-cord with terminals behind and attached to the transmitter-frame.When hung in its resting position, the watch-stem of the receiver raisesa flat spring connected with the incoming main-circuit wire from a mixedmetal post, which is united by a wire with the telephone branch circuitand establishes a metallic connection from the said spring through themetal of the said suspendingstem to the perforated holding-plate of thereceiver, this being connected by an other wire through a call-key tothe call-bell. The presence or absence of the receiving-tele phone inits place of rest thus determines the direction of the main circuitthrough the apparatus. Since to the weight of the telephone issuperadded a leverage of considerable power, it. will be seen that I amenabled to use a powerful counter-spring, and the chances of getting outof order are thus ma terially diminished. A call-key and itsbattery-contact project from a slot or orifice in the side of the frame,the former being normally in the bell-circuit, as already indicated, andthe latter being connected directly with a screw-terminal leading to avoltaic battery.

The several circuit arrangements will be fully described herein`Heretofore, as I am well aware, organizations similar in some respectsto the present have been devised; but they have been deective in thatsome have been altogether devoid of the microphonic transmitter, whileothers, endeavoring to supply this wa-nt, have introduced transmittersin which the contacts are distributed over the entire surface of thediaphragm, and thus produce inharmonious and non-concurrent vibrations,interfering with perfect articulation.

My instrument embodies a radical improvement in the switching andtransmitting apparatus and a more compact organization than anyarrangement which has heretofore been proposed, and consists, further,in the employment of a common non-conducting matrix or base-plate, whichis recessed and channeled for the reception of the transmitter elementsand electrical connections.

In the drawings which form a part of this specification, Figure l is aperspective view of the entire station apparatus ready to be screwed upon a wall or partition. Fig. 2 is a similar perspective view but withthe receiver removed. Figs. 3 and 4 are respectively' front and rearperspective views of the mold or frame within which the working partsare mounted. Fig. 5 is a vertical section on the line :c and Fig. G ahorizontal section on the line yy, of said mold. Fig. 7 is a verticalsection of the transmitting and switching apparatus. Fig. S is a rearview of the apparatus, showing the call-key and some of the electricalconnections. Fig. 9 is a line drawing of a side elevation of the entirestation apparatus, showing the switch and indicating its operation bymeans of the receivingtelephone. Fig. 10 is a detail of thecircuit-changing switch. Figs. 1l and 12 are respectively rear, face,and sectional side views of a modified mechanical arrangement in whichthe bell-call is attached directly to and forms a homogeneous part ofthe telephone outfit. Fig. I3 is a diagram of thc electrical connectionsof a telephone-station constructed in accordance with my invention; andFigs. 14 and l5 are diagrams of two station telephone-circuits, showingtwo ways of connecting the instruments.

In the principal and ordinary.7 form of the apparatus, A is a mold,base, or frame for the operating parts, and is formed of nonconductingsubstance. It may be made of hard rubber, vulcanized fiber, bonsilate,papier-mach, or similar material, and its various apertures, recesses,or channels may either be excavated or may be pressed therein while thematerial isin aplastic condition, according to the material used. Nospecific dimensions need be adopted; but I have found the size of twoand three-quarters inches square by seven eighths of an inch thick to beconvenient. This frame, divested of its attachment, is shown in Figs. 3,4,5, and 6. A recess V on the front side, furnished with a shoulder H,forms the diaphragm-seat and vocalizing-chamber of the transmitting element, the diaphragm B resting on the said shoulder, and being thereconfined by an expansible ring-shaped spring C. At the upper edgevertical channels l', 2', 3', and 4 are cut for theinsertion ofscrew-terminals l, 2, 3, and 4, these being secured by machine-screws,(see Fig. 8,) which also serve for the attachment of the internalconnection-wires. A central vertical channel 8 is provided for theline-switch spring, and a smaller channel 7 for a wire leadingl to the.call-key. These channels all thread the rear side ot' the casing, whichalso is threaded with horizontal channels 9, lO, and 13 for the call-keyand its attachments, a vertical channel 14 for the wire leading fromscrew-terminal l, and a cavity ll, in which may be mounted the inclinedfixed element of the transmitter-contacts, which are mounted on theabutment z5, ai d the cord-connections of the receivingtelephone, thesaid cord finding egress through an orifice 31. The base may befurnished at the corners of its rear side with feet l2,where by it maybe supported with its workin g parts at a suitable distance from thewallon which the apparatus is placed.

In addition to the various front and rear side recesses and channelsrecited, the base is centrally divided into narrow cells I, separatedfrom one another by the partitions J, these being integral with thesubstance of the frame, the said cells being adapted for the receptionof the movable contact-pieces of the transmitter. The construction oftransmitter IIO which I prefer in this system is that described in theseparate case to which I lhave referred, and isshown with the greatestclearness in Figs. 7, 8, 11, 12, and 13. The diaphragm B, which may bemade of any suitable material,

may form or may carry equatorially a suitable conducting-piece D,preferably of carbon. A complementary fixed conductingpiece, alsopreferably of carbon, and centrally divided so as to form two pieces Kand K', placed end to end, (but which may be in one piece, if desired,)is mounted in the form of an inclined plane and supported by its loweredge on the abutment t. Disks or short cylindrical sections, E ofcarbon, are placed in the cellsv I, which are sufficiently wide tosupport them loosely, and, as shown, 4make contact in the rear with theinclined contact-pieces K and in front with the diaphragm contact-pieceD. Themicrophonic contact thus has a gravity adjustment, the carbondisks being prevented from yielding to their tendency to roll down theinclined plane by their contact with the diaphragm-plate, and bothseries of contacts are in the telephone-circuit. By employing a numberof such disks I am enabled to eifect a considerable variation in thetelephonie the spherically-enlarged part P of the recurrentand byplacing them and also the diaphragm-plate in the equatorial positionwhich I have shown I am enabled to use a multiplicity of contactswithout distributing'them over the entire diaphragm-surface.

I employ a receiving-telephone R of ordinary construction, resembling aWatch in form and size, this having a projecting metal suspending-steml, With'a spherical enlargement P placed about midway of its length. Thereceiver is connected with the microphonecircuit by its doubleconductor-cord c, unit-l ing at one end, of course, with the terminalsof the telephone-helix (not shown) and at the other by means of itsbifurcated ends (see Fig; 8) with the appropriate telephone-circuitconnections within the recess 11 of the frame, the said cordpassing'thereinto through the oriiice 31. rlhe receiving-telephone, whennot in use, is intended to be suspended, as shown in Fig. 1, in front ofthe transmitterdiaphragm, th us keeping it out of the way and adding tothe sightliness of the appliance. To this end it has the stem l, and forthe reception of the said stein a metal plate perforated and slotted at72. and i is affixed by screws 5 and 6 to the upper edge of theframepiece and overhangs the frontV face thereof. The perforation iscircular at its outer end, and at this part is sufficiently wide toallow ceiver-stem to be easily passed through it; but it begins tonarrow at about the middle of its length, and at its inner end is muchnarrower than the diameter of the said enlargement. The plate is bentinto a right angle across the center of the perforation, so that thecircular and large part thereof is in the vertical plane, while thenarrow and slotted part is in a horizontal plane, its end being`slightly in front of the front of the framepiece. The extreme end ofthe plate a is curved backwardly, as at a', the curved portion beinglikewise slotted at t. This plate is secured t-o the frame by suitablescrews, its fixed end being likewise slotted at g, for a purpose whichhereinafter will appear. It will now be readily understood that theplate a is made to serve as a telephone-rest by the construction I havedescribed. In the act of placing the receiver therein the stem of thesaid receiver, as in Fig. 9, is horizontally passed through the circularpart of the perf foration h, the enlargement P passing therethrough. Theinstrument is thenA caused to Vassume a vertical position, and the saidenlargement, being unable topass through the slot, rests thereon, andthe receiver isthereupon suspended, as shown in dotted lines, theextreme end of the stem passing through the slot t' and maintaining avertical position therein. Asis well known in telephony, it isconvenient to provide a circuit-changer whereby the main circuit can betransferred from the signal-bell branch to the telephone branch, andreversely, and also to open and close the battery-circuit if a batterybe employed. These functions are performed by the act of removal andreplacement of the receiver in the holder which I have described and bythe use of the said holder in association with the receiver and otherattachments now to be specified. A metal post c is mount-ed upon andsecured to IOO the upper edge of the frame-piece, and is in- Y sulatedfrom the plate a by being mounted within the slot g of the horizontalpart of the said plat-e. This post c forms one terminal of thetelephone-branch circuit, and it extends to a greater distancevertically from the edge of the frame-piece than the highest point ofthe curved plate a'. A curved metal spring b of considerable stiffnessis secured at one end by screws in the vertical channel 8, and fromthence rises vertically, and at a suitable height is bent forward andoverhangs the post c and the plate a, making a strong contact with .theend of the former unless positively elevated and disengaged therefrom.The said spring, as will hereinafter be seen, forms the terminal of themain circuit. It should also be stated that the plate a forms theterminal of the call-bell branch. Now, when the receiver is in use andthe spring b presses upon the top of the post c, the main line isthereby connected with the telephone branch and the circuit of a batteryclosed through the microphone; but Ithe signal branch is open, becausethe spring b is prevented by the height of said post from reaching theplate a; but when the use of the telephone has ceased the receiver-steinZ is passed through the hole h in the plate a, and then the receiver ispushed down into the position shown in dotted lines in the iigures. Itis thus caused to act as a lever, the enlargement P, resting on thehorizontal part of the plate, being the fulcrum thereof, and the end ofits stem, rising through the slot t', strikes the end of the spring b,making contact therewith and breaking its former contact with the postc. The new position is indicated by the dotted lines in Fig. 9. The mainline is thus disconnected from the telephone-circuit and connectedthrough the substance of the metal stern of the receiver with the platea, forming the signalbranch terminal. It is not, however, absolutelynecessary, except for symmetry of appearance, that the receiver whenhung in place shall be forced down in front of the transmitter, sinceits weight alone will operate the circuit-changer. interposed in thisbranch is a call-key o, provided with a front contact or anvil p and aback or resting contact 25. These are placed in the channels 9, 10, 13,and 4 at the rear side of the instrulnent.

The electrical connections are clearly indicated by the diagram Fig. 13.Screwterminal 3 is usually connected with the main line 22, leading tothe distant station. By wire 14 it is united within the instrument tothe spring b, which, as explained, becomes the terminal of said mainline. The main line is in the diagram shown as being connected with thetelephone branch, which is traced as follows: from its terminal post cby wire 17 to inclined plate K of the microphone, through two of thecarbon disks E to diaphragmplate D, through the remaining disks to theother inclined plate K by wire 18 to receiver, then by wire 19 toscrew-terminal 1, and by wire 21 to the battery and ground at G. Thecall-bell branch is in the diagram discontinuous, (the receiver R beingoi: its holder, as hereinbefore explained,) but is traced as follows:from plate a by screw 5, wire 15, callkey o, back-contact 25 thereof,screw-terminal 4, wire 23, bell Q, and wire 24 to ground. A branch wire1G runs from terminal2 to the key-anvil p. Since the terminals 1 and 2are both connected, although by different wires 20 and 21, with thebattery M, it is clear that the same purpose would be achieved byconnecting the battery-wi re with but one of them, and then by unitingthe two terminals 5 but I prefer the two terminals connected as shownfor convenience: So, also, though I show a separate ground for thetelephone and battery and bell branches, it is obvious that in practiceone would serve for both, or that as an alternative the groundconnectionmight be dispensed with altogether and a return-wire substitutedtherefor. The bell Q may be mounted close to the other parts of theapparatus, or may be at any desired distance. It is immaterial.

Figs. l1 and 12 are modifications, in which, while the electricalconnections remain the same, the bell is affixed to a bracket Z, placedover the casing. ln this instance the springu tongue 36 andbracket-contact 37 take the place of the spring b and post c of theIirst set, the plate a being only slightly changed in form. Thetelephones remain without change; but the casing is made hollow insteadof being channeled and recessed. The non-conducting partitions J and thediskcontaining cells between them are mounted in a frame secured betweenthe diaphragm and the back of the box, to which it is fast ened byscrews. The telephone-cord epasses up into the box, and the, key isrepresented by the spring-tongue 3l,its battery-contact by the point 32,and its resting-contact by the bracket It is operated by the button 30.

Figs. 14 and 15 show modes of connecting my compound station apparatusin a telephone-circuit.

X and Y are respectively telephone-stations.

In Fig. 14 a mode of connection is shown in which but two wires r and sare required, but requiring, however, a battery at each station. At bothstations are like instrumentalities, and the connections are asindicated. At station X bindingscrews l and 2 are united by wire 20 andconnect by wire 21 with the battery M. The other pole of said battery isconnected with line r, leading to station Y,

where it diverges, the principal branch being through wire 42 to bell Qand thence by wire 44 to binding-screw 4. The other branch leads by wire21 to binding-screw 1. There is also a wire leading from binding-screw 2through battery M to the said branch wire 21. At station X, again, abranch 41 leads through call-bell Q and wire 23 to binding-screw 4 ofthe instrument there. The main-line wire s extends from thebinding-screw 3 at one station to the same screw at the other. Thestation-instruments are symbolically shown; but they are in everyrespect arranged as in the former descriptions and as in Fig. 15, and itwill readily be understood by those skilled in the art by reference tothe other drawings that each stat-ion uses its own battery in sendingcall-signals, but that the battery at station X only is used in talking.

The mode shown in Fig. 15 has but a single battery, but requires threelines. At station X binding-screws 1 and 2 are united, and togetherconnect with one pole of battery M. From the same pole of the battery isled the main line 20, leading to the binding-screw 2 at station Y. Frombinding-screw 3 at station X the main wire 22 runs to the terminal ofthe same number at station Y. From binding-screw 4 at station X a wireleads to one terminal of the call-bell Q, and thence by main wire 21 toterminal 1 at station Y. At station X a branch 23 leaves this wire 21and connects with the remaining pole of the battery, and at station Y abranch 24 leads through the call-bell Q to terminal 4.

It is scarcely necessary to describe the operation of these instruments.At each station a pressure of the key while the receivingtelephones arein place connects the main line leading to the bell at the distantstation with the battery, closing the circuit and ringing the IOO IIO

said bell. Both receivers are then taken from their holders, and thebattery-current is thereby directed through the microphones, the bellsbeing disconnected from and the telephones connected with the maincircuit. Conversation can then be carried on in a manner wellunderstood.

Having now fully described my invention, I claim- 1. The combination, ina telephone-station apparatus, of a microphonic transmitter in which thelvariable-resistance contacts are formed by the'interposition ot anumber of carbon disks placed on edge between an inclined rear surfaceof carbon and a plate of carbon carried upon the diaphragm, anonconducting case for the working parts of the said transmitter,comprising non-conducting partitions integral with or centrally mountedwithin the said case and interposed between the several adjacent carbondisks, a perforated bifurcated plate serving asa telephoneholder mountedcentrally on the upper edge of the non-conducting case, a portabletelephone-receiver having a watch-stem suspending-rod adapted to engagewith the said perforated plate, whereby the said telephone may be hungupon its holder in front of the transmitter, a circuit-chan ging switchalso mounted upon the upper edge of the said non-conducting case,actuated automatically in one direction by a spring when the receiver isremoved and actuated in the other direction by the operation of thesuspending-stem of the said receiver when replaced, the said stem actingas a lever in opposition to the said spring, as and Vfor the purposesspecified.

2. The combination, in a telephone-station outfit, of amicrophone-transmitter consisting of a vibratory diaphragm carrying orforming a conducting-plate, aninclined plane of conducting material inthe rear thereof, and a series of carbon disk-formed movablecontact-pieces making variable-resistance contact with the diaphragm andrear plates, a mold, frame, or base of non-conducting material recessedin front to serve as the ldiaphragm-seat and vocaliZing-chamber,provided centrally with partitions for interposition between the severalcarbon disks and channeled on the rear side for the reception of acalling-key and electrical connections, a

callin g-key with normal and battery contactsmounted in one ot the saidlateral channels on the rear side of said frame and projectingtherefrom, a circuit-changing switch vcomprising a line-spring, atelephonecontact, and an alarm-branch contact, serving also as atelephone-holder, secured to the upper edge of the non-conducting frame,and a portable telephone-receiver in circuit with the said microphonetransmitter provided with a watch-stem suspending-rod adapted to beengaged by the telephone-holder when placed therein and thereupon todisengage the linespring from the telephone-contact and to transfer thecircuit thereof through its own substance to the signal-branch contact,the telephone-receiver being hung in front of the transmitter-diaphragm,substantially as described.

3. As a new article of manufacture, the homogeneous case, frame, or basefor a compound telephonic apparatus described herein, consisting of ablock of hard rubber, vulcanized fiber, or like non-conducting materialpartitioned centrally for the reception and mutual insulation of theseveral movable microphonic contact-pieces, and provided with ashouldered recess at its front side, serving as the diaphragmseat andvocalizing-chamber, and with suitable channels andrecesses cut orpressed into its substance at its rear side for the reception andprotection of the callin g-key and electrical connections andte`rminals,substantially as described.

4.- In a compound telephone-station outtlt, the combination of a mainelectric circuit,

a call-signal branch circuit therefor normally completing the same andincluding a slotted plate forming a holder for the receiving-telephoneWhen not in use, a spring calling-key, the back or resting contactthereof, and a callbell magnet, a normally open or discontinuoustelephone branch including a multipleconta'ct microphone, areceiving-telephone, and a transmitter-battery, the said battery beingalso connected with the front contact of the calling-key, acircuit-changing switch for transferring the main line from eitherbranch to the other as required and for clos- IOO i-ng the circuit ofthe battery through the transmitter, operated automatically in onedirection and actuated by the suspendingstern of the telephone-receiverused as a lever in the other, and comprising a contact-springconstituting the automatically actuating main-line terminal, aninsulated contact-post forming the terminal of the telephone branchnormally out ot contact with the said mainline spring, but connectingtherewith when the receiver is removed for use, thereby closing the saidbranch to line, Vand the slotted receiver-holding plate forming theterminal of the call-signal branch circuit and normally connected withthe said main -line spring through the substance of the suspending-stemof the receiver, the said stem being interposed between the said plateand the linespring, uniting them electrically and raising the latterfrom the telephone-branch terminal post when the receiver is hunguponits holder, substantially as described.

5. The combination, in a telephone-station apparatus and in a concreteorganization of the several instrumentalities thereof, of anonconducting matrix forming a frame or base for the entire instrument,a multiple-contact microphonic transmitter mounted in the front andcenter of said matrix, a calling-key with front and back contacts,together with electrical connections recessed in channels cut in theback of said matrix, a circuit-changing switch constituting av rest orholder for IIO the receiving-telephone mounted on the upper edge of thesaid matrix and projecting over the front side thereof, and awatchformed telephone receiver having a metal suspending-stem andadapted to be hung thereby,wl1en not in use, in the said telephoneholderand in front of the transmitter, the said stem being adapted to actuatethe said switch in one direction and forming when in place a portion ofone of the circuits controlled thereby.

6. The combination, in a telephone-station apparatus, withareceiving-telephone having a metal suspending stem formed, as shown anddescribed therein, with an enlargement at its central part, of acircuit-changing switch controlling the circuits of said apparatus, andconsisting of the angle-plate a, perforated and slotted to receive andlock the telephone suspending-stem and to serve as a rest or holdertherefor and forming the terminal of a given branch circuit, theinsulated post or fiXed contact c, forming the terminal of a secondbranch circuit, and the spring b, ixed at one end, having its free endin line with and overhanging the said fixed post and the slot of theangle-plate, the said spring being the terminal of a main circuit andbeing adapted to press, when the telephone is not suspended inplace,upon the said insulated post and to be elevated and disconnectedtherefrom by the telephone suspending-stem acting as a lever and toconnect through the substance thereof with the slotted plate when thetelepho'ne is suspended from the said plate, substantially as and forthe purposes described.

In testimony whereof I have signed my name to this specification, in thepresence of tWo subscribing Witnesses, this 16th day of February, 1889.

BRUNO ABDANK-ABAKANOWICZ.

Witnesses:

Taos. D. LooKWooD, GEO. WILLIS PIERCE.

